Officials are probing how a 51-year-old highway bridge came to collapse in the Italian port city of Genoa yesterday, killing at least 26 people and injuring 16 others as it sent dozens of vehicles tumbling into a heap of concrete and twisted steel.

Hanson 'confident' of no bad Qld apples

One Nation leader Pauline Hanson is "as confident as anyone can possibly be" there are no bad apples in her batch of 36 newly-announced Queensland election candidates, but admits there are no guarantees.

The party's vetting process for the Queensland poll has also been tightened after the resignation from One Nation of maverick Senator Rod Culleton.

"We've actually knocked back some candidates," Senator Hanson said in Brisbane on Monday.

The party on Sunday announced an initial 36 candidates to contest state seats in the poll, due by early 2018, including US-born Donald Trump supporter Jane Truscott and former Liberal National Party MP Neil Symes.

"They've been through a very tight, stringent test of questions and asking where their loyalties lie," Senator Hanson said.

"I actually had a good talk with them yesterday virtually saying if you don't intend to be loyal (and) work as a team, please, you're not here."

Asked how confident she was there were no bad apples in the batch, the senator replied: "As confident as anyone can possibly be."